2 red patch under tongue, nonsmoker, oral surgeon took health hist & looked at it said don't worry about it but i'm worried could it be something worse?

Trust: Perhaps you need to discuss this in more detail with the Oral Surgeon who saw you already. If you need a second Oral Surgeon to confirm the absence of anything serious, by all means go for a second opinion. If they both agree, stop worrying.

See your dentist: There are many and various oral lesions which could match your description (traumatic erythema, Reiter disease, etc). I can appreciate your concern, but finding a proper diagnosis and treatment may be the answer to your worries. Rec.: see your dentist for further investigation or referral to oral medicine specialist.